Steam powered refrigeration system



Nov. 22, 1966 J. A. PAPAPANU 3,286,480

STEAM POWERED REFRIGERATION SYSTEM Filed Sept. 1, 1964 REFRIGERANT CONDENSER STEAM CONDENSER STEAM GENERATOR INVENTOR. J AMES A. PAPAPANU ATTURNEY United States Patent 3,286,480 STEAM POWERED REFRIGERATION SYSTEM James A. Papapanu, Syracuse, N.Y., assignor to Carrier Corporation, Syracuse, N.Y., a corporation of Delaware Filed Sept. 1, 1964, Ser. No. 393,646 3 Claims. (Cl. 62-188) This invention relates generally to a refrigeration system and to -a method of providing refrigeration and, more particularly, to a system and method for balancing power and refrigerant fluids in a refrigeration machine wherein a power fluid drives a refrigerant compressor and the refrigerant and power fluids are mixed and subsequently separated and passed to their respective sides to balance the system and for reuse in the system.

The present invention is particularly applicable for use in a heating and cooling system generally a disclosed in a copending United States patent application of Louis H. Leonard, Jr., entitled, Heating and Cooling System, Serial No. 377,258, filed June 23, 1964. Therein, cooling capacity of the system is regulated by controlled blanketing of a steam condenser with a noncondensible (refrigerant) vapor for varying the steam discharge pressure of a steam turbine section of a turbocompressor to vary in turn, the refrigerant output of the compressor section. Refrigerant vapor, and any water vapor carried thereby, is withdrawn from the steam condenser by .a purge system and passed into a cooler or evaporator which has provision for separating refrigerant and water. From the cooler, refrigerant is recirculated through the refrigerant side of the system and water may be returned, as needed, to the power side of the system.

It is a primary object of this invention to provide a new and improved refrigeration system and a method of providing refrigeration.

A further object is provision for use in a refrigeration system having a power side and a refrigerant side, of a new and improved balancing system and method for passing refrigerant fluid and power fluid between the refrigerant and power sides so that these fluids may be reused in the system and an adequate balance of the fluids is maintained throughout the system.

A more specific object is provision of a new and improved fluid balancing system for a steam powered refrigeration system including a refrigerant side having a cooler with provision for storing water, a power side including a steam generator and a steam condenser, and a steam condensate pump for passing steam from the steam condenser to the steam generator, with provision for passing water between the cooler and the steam condenser to maintain a substantially predetermined water level on the power side of the system and including conduit means having a first valve for passing water from the cooler to the steam condenser when the first valve is open and a second valve for diverting water from the steam generator to the cooler when the second valve is open, and provision for opening the first valve responsive to a predetermined low water level in the steam condenser and for opening the second valve responsive to a predetermined high water level in the steam condenser.

Another more specific object is provision of a new and improved method of balancing fluids in a steam powered refrigeration system having a cooler with provision for storing water, a steam generator in circuit with a steam condenser and a steam condensate pump for passing water from the steam condenser to the steam generator, and conduit means including a first valve for passing water from the cooler to the steam condenser when the valve is open and a second valve for passing water from the steam condensate pump to the cooler when the second valve is open, the method including the steps of passing water from the cooler to the steam condenser by opening the first valve when a predetermined low water level is reached in the steam condenser, and diverting water from the steam generator to the cooler by opening the second valve when a predetermined high water level is reached in the steam condenser.

These and other objects of the invention will be apparent from the following description and the accompanying drawing which is a flow diagram of a refrigeration system incorporating features of the invention.

The system may be considered as having a power side including a circuit for the circulation of a power fluid and a refrigerant side having a circuit for the flow of refrigerant fluid under the influence of a prime mover driven by the power fluid, with the operation of the system regulated by a control system.

The invention will be described with reference to a preferred power fluid, which is water, and a preferred refrigerant fluid which is octafluorocyclobutane, commonly referred to as C318 and having a chemical formula C F as is more fully discussed in the previously mentioned patent application. However, other power fluids and refrigerants having the desired chemical and physical properties may be utilized within the scope of this invention.

A more complete description of the system may be had from the aforementioned patent application. In brief, and with reference to the drawing, on the power side a turbo-compressor 11 has a turbine section 12 which receives steam, preferably at a constant pressure, through a steam line 13 from a steam generator 14 and discharges steam through a discharge line 15 into a steam condenser 16 including a steam condsensate chamber 17 for storing the condensate and from which the condensate is returned to the steam generator through a steam condensate line 18 by means of a steam condensate pump 19 in the line 18. On the refrigerant side a compressor section 20 of the turbocompressor 11 receives refrigerant vapor through a suction line 21 and passes the compressed vapor through a line 22 to a refrigerant condenser 23 from which the refrigerant condensate passes through a condensate line 24 to a suitable refrigerant flow restricting means such as a float valve unit 25 and then through an inlet line 26 to a cooler or evaporator 27. A chilled water line 28 communicates with -a flooded chilled water tube bundle 29 in a pan 30 in the cooler 27, and this bundle is cooled by and vaporizes liquid refrigerant in the pan. The refrigerant vapor is returned to the compressor through the suction line 21, thus completing the refrigeration cycle.

The turbocompressor 11 is preferably equipped with Water lubricated bearings. Water for lubricating the bearings passes through a lubricant water line 31 from the outlet of the steam condensate pump 19 to the turbocornpressor. Lubricant water and any leakage of refrigerant from the compressor passes through a drain line 32 and into the steam condenser 16.

Cooling capacity of the refrigeration system is regulated by regulating the condensing capacity of the steam condenser 16 to vary its pressure and therefore the discharge pressure of the turbine 12, thus varying the turbocompressor output, and more particularly, the refrigerant output of the compressor 20.

Steam condenser pressure is regulated by con-trolled blanketing of a steam condensing tube bundle (not shown) with a n-oncondensi-ble (refrigerant) vapor introduced into the steam condenser through a refrigerant line 33 from the cooler 27, and this line has a modulating refrigerant valve 34 controlled responsive to chilled water temperature as by a sensor 35 on the chilled water line 28. As the coool-ing requirement drops, the chilled water temperature also drops and the sensor 35 causes the valve 34 to open sufficiently to increase the blanketing within the steam condenser 16 and thereby increase the condenser and turbine discharge pressures to reduce the output of the turbocompressor 11, thus reducing the cooling capacity of the system. Conversely, should the cooling requirement increase, the sensor 35 closes the valve 34 sufficiently to reduce the blanketing within the steam condenser 16, thus reducing the turbine back pressure and increasing the output of the turbocompresso-r 11 to increase the cooling capacity of the system.

The balancing system includes a purge system having a purge line 36 opening into the steam condensate chamber 17 for withdrawing refrigerant vapor and any water vapor carried thereby from the steam condenser 16, preferably at a constant rate. The purge line 36 opens into a throat portion of a jet pump 37 positioned in a water sump 38 for discharging the entrained refrigerant vapor into the cooler. The sump 38 provides a water storage container in a lower portion of the cooler 27. A water supply pump 39 has its inlet connected with the cooler sump 38 by means of a line 40 and an outlet connected with the jet pump 37 by means of a line 41 to provide impeller water for operating the jet pump and recirculating the water through the cooler sump. Hot vapor from the steam condenser 16 maintains the sump 38 preferably at least F. above the temperature of a refrigerant chamber 42 overlying pan 30 in an upper portion of the cooler 27, so that refrigerant injected into the sump 38 is a vapor and passes upwardly about the pan and into the refrigerant chamber for return to the compressor 20 through the suction line 21 which opens into the refrigerant chamber. Any water passing with the liquid refrigerant into the pan 30 through the line 26, or condensing in the refrigerant chamber 42 and settling onto the liquid refrigerant in the pan, passes to the left end of the pan and through a suitable weir or port 43 and into the sump 38.

In order to maintain a desired predetermined quantity of water on the power side of the system, a first water line 44 is provided between the outlet of the water supply pump 39 and the steam condensate chamber 17. A normally closed first solenoid operated shut-off valve 45 in the first water line 44 is opened when the condensate level in the steam condensate chamber 17 drops to a predetermined low level so that the water supply pump 39 may pass water from the cooler sump 38 into the condensate chamber 17. Herein, the first valve 45 is operated by a first sensor 46 including a pair of electrical probes, a first of the probes 47 being at a low elevation for opening the valve 45 when the water level drops below this probe, and a second probe 48 being at a higher elevation for closing the valve when the water level rises to engage the second probe.

In order to pass water from the steam condenser to the cooler, a second water line 49 having a second normally closed solenoid actuated valve 50 is provided between the outlet of the steam condensate pump 19 and the throat of a second jet pump 51 which receives impeller water from the outlet of the water supply pump 39 and has its discharge opening into the cooler sump by means of a line 52. A second sensor 54 includes a third probe 55 at a high elevation, but below the opening of the purge line 36 into the condensate chamber 17 so that water is not drawn through the purge line. When the third probe 55 is engaged by the water, the second sensor is operative for opening the second valve 50 and for maintaining the second valve open until the water level drops below a fourth probe 56 at a lower elevation than the third probe 55 and above the elevation of the first probe 48. The sensors 46 and 54 may be of any suitable type, and are commercially available. Thus, water may be diverted from the steam generator 14 to the cooler 27 should the water level in the steam condensate chamber 17 rise too high.

During start-up of the system, the second jet pump 51 utilizes the output Of the water supply pump 39 to raise the pressure of the water passing from the steam condenser 16 through the second water line 49 sufficiently to overcome a relatively high difference in pressure developed between the steam condenser 16 and the cooler 27. During normal cooling operation, the cooler pressure is about 5 p.s.i.g. and the steam condenser pressure is about 27 Hg, but at the beginning of start-up both the steam condenser and the cooler pressures may be in the neighborhood of 50 p.s.i.g. Under code requirements, the steam generator 14 is not started in operation until the steam condenser pressure drops to about 15 p.s.i.g., for example, and therefore the steam condenser pressure drops substantially below the cooler pressure before the cooler pressure beings to drop when the turbocompressor is rendered operative responsive to operation of the steam generator. The steam condensate pump 19 may normally provide a lift of about 25 p.s.i.g., for example, so that as the purge system reduces the steam condenser pressure to 15 p.s.i.g., the steam condensate pump is unable to pass water from the steam condenser to the cooler, or to pass the water at a sufficient rate. The jet pump 51 may lift the water pressure 10 to 20 p.s.i.g., for example, and thus with the steam condensate pump, overcome the pressure differential between the steam condenser and the cooler which may develop during start-up.

Thus, refrigerant is returned from the power side to the refrigerant side through the purge system, and water is passed between the refrigerant side and the power side through the water lines, as 44 and 49, to maintain a desired predetermined quantity of water on the power side.

While a preferred embodiment of the invention has been described and illustrated, it will be understood that the invention is not limited thereto since it may be otherwise embodied within the scope of the following claims.

I claim:

1. A fluid balancing system for a steam powered refrigeration system, comprising the combination of, a refrigerant side having provision for collecting Water; a power side including a steam condenser having means for collecting water, means including a steam driven engine for operating the refrigerant side and in circuit for discharging steam into the steam condenser, and means including a steam condensate pump for withdrawing the condensate from the steam condenser; and means for balancing water and refrigerant on the power and refrigerant sides and including, first valve means for passing water from said refrigerant side to said power side when said first valve means is open, second valve means for passing water from said steam condensate pump to said refrigerant side when said second valve means is open, and operating means for opening said first valve means when a predetermined low water level exists on said power side and for opening said second valve means when a predetermined high water level exists on said power side.

2. A fluid balancing system for a steam powered refrigeration system, comprising the combination of, a refrigerant side including a cooler having provision for storing water; a power side including a steam condenser, and a steam driven engine to operate the refrigerant side and in circuit for discharging steam to the steam condenser, and means including a steam condensate pump for withdrawing the condensate from the steam condenser; and means for balancing water and refrigerant on the power and refrigerant sides and including, means for passing refrigerant vapor from the steam condenser to the cooler, and means for passing water between said cooler and said steam condenser to maintain a substantially predetermined water level on the power side of the system and including, conduit means including first valve means between said cooler and said steam condenser for passing water from said cooler to said steam condenser when said first valve means is open, and second valve means between the outlet of said steam condensate pump and said cooler for passing water from said steam condenser to said cooler when said second valve means is open,

and operating means for opening said first valve means responsive to a predetermined low water level in said steam condenser and for opening said second valve means responsive to a predetermined high water level in said steam condenser.

3. A fluid balancing system for a steam powered refrigeration system, comprising the combination of, a refrigerant side including a cooler having provision for separating Water and refrigerant and storing the water, and a refrigerant compressor in circuit with said cooler for circulating refrigerant through the cooler during cooling operation; a power side including a steam generator and a steam condenser, and a steam driven engine in circuit for receiving steam from the steam generator and discharging steam to the steam condenser to operate the compressor, and means including a steam condensate pump for passing the condensate from the steam condenser :to the steam generator; and mean for balancing water and refrigerant on the power and refrigerant sides and including, first and second jet pumps in circuit for discharging into said cooler, a water pump in circuit for receiving water from said cooler and for passing impeller water to said jet pumps, means for passing refrigerant vapor from the steam condenser to the cooler and including a purge line between said steam condenser and said first jet pump, and means operable for passing Water between said cooler and said steam condenser to maintain a substantially predetermined water level on the steam side of the system and including, first conduit means including first valve means between the outlet of said water supply pump and said steam condenser for passing water from said cooler to said steam condenser when said first valve means is open, and second conduit means including second valve means between the outlet of said steam condensate pump and said second jet pump for passing steam condensate from said steam condenser to said cooler when said second valve means is open, first operating means for opening said first valve means re sponsive to a predetermined low water level in said steam condenser and closing said first valve means responsive to a higher water level in said steam condenser, and second operating means for opening said second valve means responsive to a predetermined high water level in said steam condenser and closing said second valve means at a lower water level above said low water level in said steam condenser.

References Cited by the Examiner UNITED STATES PATENTS 677,845 7/1901 Coleman 62502 1,102,998 7/1914 Coleman 62501 X 2,183,821 12/1939 Nelson 6279 3,199,310 8/1965 Schlichtig 62502 X ROBERT A. OLEARY, Primary Examiner.

W. E. WAYNER, Assistant Examiner. 

1. A FLUID BALANCING SYSTEM FOR A STREAM POWERED REFRIGERATION SYSTEM, COMPRISING THE COMBINATION OF, A REFIRGERANT SIDE HAVING PROVISION FOR COLLECTING WATER; A POWER SIDE INCLUDING A STEAM CONDENSER HAVING MEANS FOR COLLECTING WATER, MEANS INCLUDING A STEAM DRIVEN ENGINE FOR OPERATING THE REFRIGERANT SIDE AND IN CIRCUIT FOR DISCHARGING STEAM INTO THE STEAM CONDENSER, AND MEANS INCLUDING A STEAM CONDENSATE PUMP FOR WITHDRAWING THE CONDENSATE FROM THE STEAM CONDENSER; AND MEANS FOR BALANCING WATER AND REFRIGERANT ON THE POWER AND REFRIGERANT SIDES AND INCLUDING, FIRST VALVE MEANS FOR PASSING WATER FROM SAID REFRIGERANT SIDE TO SAID POWER SIDE WHEN SAID FIRST VALVE MEANS IS OPEN, SECOND VALVE MEANS FOR PASSING WATER FROM SAID STEAM CONDENSATE PUMP TO SAID REFRIGERANT SIDE WHEN SAID SECOND VALVE MEANS IS OPEN, AND OPERATING MEANS FOR OPENING SAID FIRST VALVE MEANS WHEN A PREDETERMINED LOW WATER LEVEL EXISTS ON SAID POWER SIDE AND FOR OPENING SAID SECOND VALVE MEANS WHEN A PREDETERMINED HIGH WATER LEVEL EXISTS ON SAID POWER SIDE. 